How to conditionally run an empty build?

Due to the bug in Travis that prevents my branches from being triggered in the “Trigger Build” modal unless they’ve already been run via pushing on that branch (link), I would like to have Travis kick off a job when a branch is pushed that just runs the following script:
echo "Please ignore this build! It's a workaround for a Travis bug."

Here is my .travis.yml file:

if: type = cron OR type = api
dist: trusty
language: ruby
rvm: 2.4.1
services: docker
cache: bundler
bundler_args: --without development
before_install:
  - gem update --system
  - gem --version
after_script: docker-compose down
env:
  global: QA_WEB_HOST="stage"

matrix:
  include:
  - name: "Patient Portal: Billing Information"
    env: APP_NAME=patient_portal
    script: bundle exec rspec spec/features/tests/md_patient_portal/md_patient_billing_check_spec.rb
    # numerous other jobs
    # ...
if: NOT (type = cron OR type = api)
matrix:
  include:
    script: echo "Please ignore this build, it's a workaround for a Travis bug"

Although in the second conditional the large build matrix has been overwritten with a single job that does an echo, the Travis worker is still doing ruby/bundling/docker setup. What values should I assign to these keys so it doesn’t execute those steps? Or how can I unset all of those and just pass the Travis worker an empty hash when it parses the YAML block from the second conditional, is there some indentation trick I could use?